A rotational support vector machine (RotSVM) ensemble classifier using single-channel EEG achieved 84.46% sensitivity and 91.1% accuracy for five-stage sleep classification.
An ensemble SVM method using single-channel EEG provides high accuracy and sensitivity for automated five-stage sleep classification, suggesting utility for medical and home-care sleep monitoring.
Effect estimate: Cohen's kappa 0.88
Sleep scoring is used as a diagnostic technique in the diagnosis and treatment of sleep disorders. Automated sleep scoring is crucial, since the large volume of data should be analyzed visually by the sleep specialists which is burdensome, time-consuming tedious, subjective, and error prone. Therefore, automated sleep stage classification is a crucial step in sleep research and sleep disorder diagnosis. In this paper, a robust system, consisting of three modules, is proposed for automated classification of sleep stages from the single-channel electroencephalogram (EEG). In the first module, signals taken from Pz-Oz electrode were denoised using multiscale principal component analysis. In the second module, the most informative features are extracted using discrete wavelet transform (DWT), and then, statistical values of DWT subbands are calculated. In the third module, extracted features were fed into an ensemble classifier, which can be called as rotational support vector machine (RotSVM). The proposed classifier combines advantages of the principal component analysis and SVM to improve classification performances of the traditional SVM. The sensitivity and accuracy values across all subjects were 84.46% and 91.1%, respectively, for the five-stage sleep classification with Cohen's kappa coefficient of 0.88. Obtained classification performance results indicate that, it is possible to have an efficient sleep monitoring system with a single-channel EEG, and can be used effectively in medical and home-care applications.
Aličković et al. (2018) studied Sleep disorders. Rotational support vector machine (RotSVM) ensemble classifier vs. Traditional SVM was evaluated on Five-stage sleep classification accuracy (Cohen's kappa 0.88). A rotational support vector machine (RotSVM) ensemble classifier using single-channel EEG achieved 84.46% sensitivity and 91.1% accuracy for five-stage sleep classification.